By way of background, touch screen is becoming important in today's electronic age and is quickly becoming the primary way for users to interact with computers and smart phones. The success of Apple iPad, iPhone, Google Android and Samsung Galaxy devices underlines the general industry trend. A touch screen is an electronic visual display that can detect the presence and location of a touch within the display area. The term generally refers to touch or contact to the display of the device by a finger or hand. Touch screens can also sense, other passive objects, such as a pen. However, if the object sensed is active, as with a light pen, the term touch screen is generally not applicable. The ability to interact physically with what is shown on a display (a form of “direct manipulation”) typically indicates the presence of a touch screen.
The touch screen has two main attributes. First, it enables one to interact with what is displayed directly on the screen, where it is displayed, rather than indirectly with a mouse or touchpad. Secondly, it lets one do so without requiring any intermediate device, again, such as a stylus that needs to be held in the hand. Such displays can be attached to computers or, as terminals, to networks. They also play a prominent role in the design of digital appliances such as the personal digital assistant (“PDA”), satellite navigation devices, mobile phones, and video games.
Currently touch screens utilize the following technology: A resistive touch screen panel is composed of several layers where the most important of which are two thin, metallic, electrically conductive layers separated by a narrow gap. When a finger presses down on a point on the panel's outer surface, the two metallic layers become connected at that point and the panel then behaves as a pair of voltage dividers with connected outputs. As a result, this causes a change in the electrical current which is registered as a touch event and sent to the controller for processing.
A capacitive touch screen panel consists of an insulator such as glass, coated with a transparent conductor such as indium tin oxide. Because the human body is also a conductor, touching the surface of the screen results in a distortion of the body's electrostatic field which in term is measurable as a change in capacitance. Currently there are different technologies that may be used to determine the location of the touch. The location then can be passed to a computer running a software application, which will calculate how the user's touch relates to the computer software. In surface capacitance technology, only one side of the insulator is coated with a conductive layer. A small voltage is applied to the layer, resulting in a uniform electrostatic field. When a conductor, such as a human finger, touches the uncoated surface, a capacitor is dynamically formed. The sensor's controller can determine the location of the touch indirectly from the change in the capacitance as measured from the four corners of the panel. As it has no moving parts, it is moderately durable but has limited resolution, is prone to false signals from parasitic capacitive coupling, and needs calibration during manufacture. This is most often used in simple applications such as industrial controls and kiosks.
Another technology is Projected Capacitive Touch technology or the PCT technology. It is basically a capacitive technology that permits more accurate and flexible operation, by etching the conductive layer. Here, an XY array is formed either by etching a single layer to form a grid pattern of electrodes, or by etching two separate, perpendicular layers of conductive material with parallel lines or tracks to form the grid. When applying voltage to the array, it creates a grid of capacitors. Bringing a finger or conductive stylus close to the surface of the sensor changes the local electrostatic field. The capacitance change at every individual point on the grid can be measured to accurately determine the touch location. The use of a grid permits a higher resolution than resistive technology and also allows multi-touch operation. Examples of consumer devices using projected capacitive touchscreens includes Apple Inc.'s iPhone and iPod Touch. Other technologies include optical imaging technology, dispersive signal technology, and acoustic pulse recognition.
Even though touch screen devices are more popular than ever, inputs for touch screens have been problematic. Touch screen devices generally lack common input devices found on home consoles/computers. The analog control and buttons found on game controls are two commons inputs not found on many touch screen devices.
Current touch screen devices have the following options when it comes to these kinds of controls for input. The first type includes controls that are build directly into the device. (Example: Blackberry devices with attached physical keyboard and control ball.) Said controls make the device unnecessarily large, thereby making the device more expensive/unable to replace if controls break. In addition, these built in controls may be very small and hard to operate. They also consume power to operate, thereby reducing battery life of the main device. The second type is a plug-in device. One example of such device would be an external attached “flip open” keyboard. The problem associated with this type of solution is that it makes the device unnecessarily large due to the necessary inputs such as USB cable connectors and/or bluetooth transmission technologies, which consume more power to operate. It is also much more expensive to produce since it contains numerous electronic parts. The third type of controls are capable of virtual input to the touch screen device. Examples of such controls are the virtual keyboard found on many of the smart phone devices in the market today. The primary flaw with this technology is that it takes up valuable touch screen real estate. It is also very difficult for the user to apply control since the inputs are purely virtual and thus, there is no physical component to touch. Said technology is usually small and harder to operate easily and effectively. As a result of the aforementioned, the market now demands an efficient user friendly physical control that can easily integrate with a variety of virtual controls, thereby making the user's experience more efficient and accurate. Valuable screen space on the touch screen devices is maximized when the subject invention is utilized via minimizing any on-screen controls.